According to Andrew Newberg and Robert Waldman in Why We Believe What We Believe, we form our beliefs using four methods. First, we use evidence. We have first hand experience of something.
Second, we use logic. If this, then that.
Third, we use emotion. A strong emotional reaction creates an association.
Finally, we use society. Social expectation and/or belief, influences our beliefs.
What beliefs are you holding onto? Can you see how they might have been created?